Viral-induced cirrhosis: grading of severity using MR imaging.

OBJECTIVE: The purpose of this study was to determine whether MR imaging can be used to grade the severity of cirrhosis. MATERIALS AND METHODS: The MR examinations of 46 patients with cirrhosis were retrospectively reviewed independently by two radiologists and correlated with clinical severity assessed by Child-Pugh classification. MR imaging analysis by reviewers who were unaware of clinical status included comparison of volume indexes (computed as the product of three axis measurements) of the spleen and each segment of the liver, and changes in hepatic contour, iron or fat deposition, and presence of varices and collaterals. RESULTS: Volume index of the spleen and the presence of ascites and varices were significantly and positively correlated (p = .008, .002, .0001, respectively) with the clinical severity of cirrhosis (Child-Pugh classifications), and volume indexes of the posterior, medial, and lateral segments of the liver were significantly and inversely correlated (p = .001, .049, .041, respectively). On an MR scoring system based on four items (volume index of the spleen; volume index of posterior + medial + lateral segments; presence of ascites; and presence of varices and collaterals), averaged total MR scores were 2.5 +/- 0.3, 4.9 +/- 0.6, and 7.9 +/- 0.8 for Child-Pugh grades A, B, and C, respectively (p < .0001). The accuracy of MR scoring in distinguishing between clinical Child-Pugh grade A cirrhosis and further grades was 89%, the sensitivity was 93%, and the specificity was 82%. CONCLUSION: An MR scoring system can be used to grade the severity of cirrhosis.     

Fluid shear stress induces less calcium response in a single primary osteocyte than in a single osteoblast: implication of different focal adhesion formation.

The immediate calcium response to fluid shear stress was compared between osteocytes and osteoblasts on glass using real-time calcium imaging. The osteoblasts were responsive to fluid shear stress of up to 2.4 Pa, whereas the osteocytes were not. The difference in flow-induced calcium may be related to differences in focal adhesion formation. INTRODUCTION: To explore the immediate response to mechanical stress in a bone cell population, we examined flow-induced calcium transients. In addition, the involvement of focal adhesion-related calcium transients in response to fluid flow in the cells was studied. MATERIALS AND METHODS: Bone cells were isolated from 16-day-old embryonic chicken calvaria by serial treatment with EDTA and collagenase. Single cells on glass without intercellular connections were subjected to fluid flow, and intracellular calcium concentration was measured using imaging with fluo-3. The identification of cell populations in the same field was performed with a chick osteocyte-specific antibody, OB7.3, and an alkaline phosphatase substrate, ELF-97, for osteoblast identification afterward. Immunofluorescence staining of vinculin was performed to visualize focal adhesions. RESULTS: The percentage of cells responding to fluid shear stress at 1.2 Pa was 5.5% in osteocytes, 32.4% in osteoblasts, and 45.6% in OB7.3/ELF-97-negative cells. Furthermore, osteoblasts and OB7.3/ELF-97-negative cells were more responsive to 2.4 Pa than 1.2 Pa, whereas osteocytes were less responsive. The elevation of calcium transients over baseline did not show any significant differences in the populations. To elucidate the mechanism accounting for the fact that single osteocytes are less sensitive to fluid shear stress of up to 2.4 Pa than osteoblasts, we studied focal adhesion-related calcium transients. First, we compared focal adhesion formation between osteocytes and osteoblasts and found a larger number of focal adhesions in osteoblasts than in osteocytes. Next, when the cells were pretreated with GRGDS (0.5 mM) before flow treatment, a significant reduction of calcium transients in osteoblasts (18%) was observed, whereas calcium transients in osteocytes were not changed by GRGDS. Control peptide GRGES did not reduce the calcium transients in either cell type. Furthermore, we confirmed that osteoblasts in calvaria showed a marked formation of vinculin plaques in the periphery of the cells. However, osteocytes in calvaria showed faint vinculin plaques only at the base of the processes. CONCLUSIONS: On glass, single osteocytes are less sensitive to fluid shear stress up to 2.4 Pa than osteoblasts. The difference in calcium transients might be related to differences in focal adhesion formation. Shear stress of a higher magnitude or direct deformation may be responsible for the mechanical response of osteocytes in bone.     

Osteoblasts derived from osteophytes produce interleukin-6, interleukin-8, and matrix metalloproteinase-13 in osteoarthritis

To clarify the significance of the osteophytes that appear during the progression of osteoarthritis (OA), we investigated the expression of inflammatory cytokines and proteases in osteoblasts from osteophytes. We also examined the influence of mechanical stress loading on osteoblasts on the expression of inflammatory cytokines and proteases. Osteoblasts were isolated from osteophytes in 19 patients diagnosed with knee OA and from subchondral bone in 4 patients diagnosed with femoral neck fracture. Messenger RNA expression and protein production of inflammatory cytokines and proteases were analyzed using real-time RT-PCR and ELISA, respectively. To examine the effects of mechanical loading, continuous hydrostatic pressure was applied to the osteoblasts. We determined the mRNA expression and protein production of IL-6, IL-8, and MMP-13, which are involved in the progression of OA, were increased in the osteophytes. Additionally, when OA pathological conditions were simulated by applying a nonphysiological mechanical stress load, the gene expression of IL-6 and IL-8 increased. Our results suggested that nonphysiological mechanical stress may induce the expression of biological factors in the osteophytes and is involved in OA progression. By controlling the expression of these genes in the osteophytes, the progression of cartilage degeneration in OA may be reduced, suggesting a new treatment strategy for OA.     

Expression of cyclooxygenase-1 and cyclooxygenase-2 in human esophageal mucosa, dysplasia and carcinoma.

OBJECTIVE: COX (cyclooxygenase), a prostaglandin H synthase, catalyzes the rate-limiting step in prostaglandin biosynthesis. Two isoforms of COX have been identified: COX-1 and COX-2. We examined the expression of COX-1 and COX-2 in esophageal normal mucosa, dysplasia and squamous cell carcinoma (SCC). METHODS: The expression of COX-1 and COX-2 in 80 surgically removed esophagi due to SCC, as well as in 5 human esophageal SCC cell lines was analyzed, using immunohistochemistry and Western blot analyses. RESULTS: COX-1 and COX-2 were variably expressed in the SCC cell lines. Higher COX-1 expression was noted in 31 (41.9%) of the 74 specimens of normal mucosa, in none of the 40 specimens of dysplastic mucosa and in 15 (18.8%) of the 80 specimens of SCC, the frequency being significantly higher in normal mucosa than in dysplasia or SCC (p < 0.0001, p = 0.0018, respectively). COX-1 expression was significantly higher in well-differentiated SCC than in moderately or poorly differentiated SCC (p < 0.01). Higher COX-2 expression was noted in none (0.0%) of the specimens of normal mucosa, in 12 (30%) of the specimens of dysplastic mucosa, and in 41 (51.3%) of the speciments of SCC, the frequency being significantly higher in SCC than in normal mucosa or dysplasia (p < 0.0001, p = 0.0278, respectively). CONCLUSIONS: COX-1 is expressed in normal esophageal mucosa and is occasionally induced in well-differentiated SCC, whereas COX-2 expression is more characteristic of dysplasia and carcinoma than of normal mucosa, implying a possible association with cell differentiation in the former, and esophageal tumorigenesis in the latter.     

Relation of total and beverage-specific alcohol intake to body mass index and waist-to-hip ratio: A study of self-defense officials in Japan

We investigated the independent associations of total and beverage-specific ethanol consumption with body mass index (BMI) and waist-to-hip ratio (WHR) in middle-aged Japanese males, because of the scarcity of epidemiologic data in Japan. The subjects were 2227 male self-defense officials who received a pre-retirement health examination at the Self-Defense Forces Fukuoka, Kumamoto, and Sapporo Hospitals. Data on alcohol intake, smoking, physical activity, and past medical history were obtained from a self-reported questionnaire. Height, weight, and waist and hip girth measurements were obtained at the examination. Multiple linear regression analysis was employed. Alcohol intake was positively and strongly associated with WHR (p = 0.0001), but not associated with BMI after adjustment for lifestyle variables, including either BMI or WHR. Subjects who consumed 15 ml per day or more of shochu ethanol showed a larger WHR than never drinkers, and a dose-response relationship was found. Dose-response relationships to other beverages were not found. Dose-response relationships to other beverages were not found. These findings suggest that alcohol intake is strongly and independently associated with WHR, but not with BMI. Abdominal obesity was positively associated with shochu ethanol, but not with other types of alcohol.     

Urinary excretion of lignans and isoflavonoid phytoestrogens in Japanese men and women consuming a traditional Japanese diet.

Epidemiologic studies revealed low mortality in hormone-dependent cancer in Japanese women and men consuming a traditional diet. We previously found that certain diphenolic food components, lignans and isoflavonoids, which are converted to biologically active hormone-like substances by intestinal microflora, may be cancer-protective agents. Therefore, we studied urinary excretion of these compounds (enterolactone, enterodiol, daidzein, equol, and O-desmethylangolensin) in 10 women and 9 men in a rural village south of Kyoto, Japan. The subjects consumed a typical low-fat diet with much rice and soy products, fish, and vegetables. An isotope-dilution gas chromatographic-mass spectrometric method was used for the assays. The urinary excretion of lignans was low but that of the isoflavonoids was very high. The excretion of isoflavonoids correlated with soybean-product intake. The low mortality in breast and prostate cancer of Japanese women and men, respectively, may be due to the high intake of soybean products.     

Effects of propafenone on electrical and mechanical activities of single ventricular myocytes isolated from guinea-pig hearts.

1. The effects of propafenone on the transmembrane action potential and sarcomere shortening during twitch contraction were investigated in single ventricular myocytes isolated from guinea-pig hearts. 2. Propafenone at low concentrations (3-5 x 10(-7) M) slightly lengthened action potential duration (APD), but shortened it at higher concentrations. The shortening of APD was accompanied by an attenuation of sarcomere shortening during twitch contraction. 3. Propafenone (greater than 10(-6) M) caused a concentration-dependent decrease in the maximum upstroke velocity (Vmax) of the action potential. In the presence of propafenone (3 x 10(-6) M), trains of stimuli led to an exponential decline in Vmax. A time constant for the recovery of Vmax from the use-dependent block was 4.8 s. 4. In myocytes treated with propafenone (3 x 10(-6) M), the Vmax of test action potentials preceded by the conditioning clamp pulses to 0 mV was progressively decreased by increasing the duration of single clamp pulse or by increasing the number of multiple brief clamp pulses. 5. These findings suggest that propafenone has use-dependent inhibitory action on the sodium channel by binding to the channel during both activated and inactivated states, and that the unbinding rate is comparable to that of Class-I antiarrhythmic drugs with intermediate kinetics. Propafenone may also have an inhibitory action on calcium and potassium channels.